The present invention generally relates to cooling systems of the type generally used for the cooling of livestock and more specifically to a programmable system for efficiently using cooling fans to create an environment which protects the health and productivity of animals.
It is known in animal agriculture to cool livestock by the utilization of cooling fans. The known cooling systems typically use either fixed mounted fans, or fans which may be rotated about a vertical axis such that the angular orientation of the air flow from the fans may be varied along a horizontal plane, in either a fixed or oscillating manner. While the air flow from a fan may disperse in a variety of directions, particularly where diffusers are utilized, axial-flow fans have blades which force air to move parallel to the shaft about which the blades rotate. This direction, defined by the position of the fan shaft, is referred to herein as the axial flow direction, or simply “axial flow”. While such livestock systems may include some provision for adjustment of the vertical orientation of the axial flow, there is no known system which provides for large (i.e. greater than 45 degrees) or programmed simultaneous changes in the axial flow of a fan array along a vertical plane.
There are advantages to such functionality. The inventor herein has determined that having the ability to induce vertical changes in the axial flow allows compensating the air/mist flow from the fan for varying wind speeds and directions. Livestock cooling fans are, by necessity, typically mounted higher than the animals and mounted at a fixed angle on the vertical plane so that the axial flow is directed towards the animals. This orientation works well when winds are light or calm, but as wind speeds increase, or the wind direction changes, it is quite common for the air (and, if applicable, mist/fog) generated by the fans to be blown away before it can reach the animals.
The present invention allows the fans, and thus the axial flow, to be repositioned on the vertical plane to compensate for the speed and direction of the wind and thus optimize the cooling air/mist reaching the animals.
As another advantage, the fans may be “parked” in a completely vertical orientation where the fan blade is subjected to little or no wind, which prevents free-wheeling of the fan and reduces starting torque. This functionality further allows the fan units to be turned such that the fan units are completely facing downward, which increases the clearance for bringing machinery into the livestock structure, such as scraper tractors utilized to manage manure within the structure.
There are design difficulties which make such a system difficult and/or expensive to install which the inventor herein has overcome. If a cooling fan system includes multiple fan units having parallel axial flows and mist dispersion, electrical and water connections must be made to each fan unit. As shown in a variety of references, such as in U.S. Pat. Nos. 6,588,372, 6,578,828, and 6,883,251 (Terrell et al.), where multiple fans rotate about a vertical axis, the axial flows of the fans may be simultaneously controlled by using horizontally oriented linkage or cables. The use of such horizontally oriented members is readily compatible with the livestock structure, where the linkage or cables may be guided or attached to horizontal beams in the livestock structure. In these types of application, electrical leads may be provided with sufficient length and slack to allow rotation of the air flow vector about a horizontal plane. These references also show that if the fans utilize water for mist/fog generation, flex line may be utilized for water delivery to allow for the required length and slack of the desired rotation about the horizontal plane.
However, for rotation about a horizontal axis (referred to hereafter as vertical rotation), particularly a rotation which exceeds a change of axial flow direction of over ninety degrees, there are potential problems with achieving simultaneous rotation, as well as in providing the required delivery of electricity and water to each fan unit.